New mystery on Mars' forgotten plains

Oct 12, 2011

THEMIS daytime infrared image mosaic (courtesy of ASU/NASA/JPL) of Mars with north is at the top. Image is centered at 116.3°E and 25.0°S

(PhysOrg.com) -- One of the supposedly best understood and least interesting landscapes on Mars is hiding something that could rewrite the planet's history. Or not. In fact, about all that is certain is that decades of assumptions regarding the wide, flat Hesperia Planum are not holding up very well under renewed scrutiny with higher-resolution, more recent spacecraft data.

"Most scientists don't want to work on the flat things," noted geologist Tracy Gregg of University at Buffalo, State University of New York. So after early Mars scientists decided Hesperia Planum looked like a lava-filled plain, no one really revisited the matter and the place was used to exemplify something rather important: The base of a major transitional period in the geologic time scale of Mars. The period is aptly called the Hesperian and it is thought to have run from 3.7 to 3.1 billion years ago.

But when Gregg and her student Carolyn Roberts started looking at this classic Martian lava plain with modern data sets, they ran into trouble.

"There's a volcano in Hesperia Planum that not many people pay attention to because it's very small," Gregg said. "As I started looking closer at the broader region -- I can't find any other volcanic vents, any flows. I just kept looking for evidence of lava flows. It's kind of frustrating. There is nothing like that in the Hesperia Planum."

"A likely cause of this trouble is the thick dust that blankets Hesperia Planum," she said. "It covers everywhere like a snowfall."

So she turned her attention to what could be discerned on Hesperia Planum: about a dozen narrow, sinuous channels, called rilles, just a few hundred meters wide and up to hundreds of kilometers long. These rilles have no obvious sources or destinations and it is not at all clear they are volcanic.

NASA/GSFC/Arizona State University Lunar Reconnaissance Orbiter image "Secrets of Schröteri" Vallis Schröteri is a sinuous rille on the moon; its inner rille diverges from the primary rille near arrow.

"The question I have is what made the channels," said Gregg. Was it water, lava, or something else? "There are some lavas that can be really, really runny. And both are liquids that run downhill." So either is a possibility.

To begin to sort the matter out, Gregg and Roberts are now looking for help on the Moon. Their preliminary findings will be presented Wednesday, 12 October at the Annual Meeting of The Geological Society of America in Minneapolis.

"On the Moon we see these same kinds of features and we know that water couldn't have formed them there," Gregg said. So they are in the process of comparing channels on the Moon and Mars, using similar data sets from different spacecraft, to see if that sheds any light on the matter. She hopes to find evidence that will rule out water or lava on Hesperia Planum.

"Everybody assumed these were huge lava flows," said Gregg. "But if it turns out to be a lake deposit, it's a very different picture of what Mars was doing at that time." It would also make Hesperia Planum a good place to look for life, because water plus volcanic heat and minerals is widely believed to be a winning combination for getting life started.

"The 'volcanic' part is an interpretation that's beginning to fall apart," said Gregg. "What is holding up is that the Hesperian marks a transition between the Noachian (a time of liquid water on the surface and the formation of lots of impact craters) and the Amazonian (a drier, colder Mars)."

She has found that other scientists are interested in her work because of its possible implications on the Mars geological time scale. Gregg is not worried that Mars history will need to be rewritten, but she does suspect that Hesperia Planum is a lot more complicated than people has long thought.

Deposits of volcanic ash colour this view of the Meridiani Planum, as seen by the Mars Express High Resolution Stereo Camera. They also give clues to the prevailing wind direction in this region of Mars.

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David Talbott has been pointing this out for quite some time now in the various Electric Universe TPOD's. In fact, the Grand Canyon appears to share the same problems of these foreign rilles -- including the fact that the Colorado River punches straight through the Kaibab Upwarp (a plateau) -- which, technically speaking, is not supposed to happen.

"The face of the earth presents many problems for geologists, not the least of which is that the Grand Canyon is supposed to have been formed by the Colorado River. As recently as six years ago geologists were working with four different and mutually exclusive models of the canyon's creation. At a special meeting they managed to winnow the four theories down to twoneither one of them satisfactorywith more than one reason to refute them both. One geologist noted that the only way the Colorado River could have carved the canyon is if it came out of the sky."

What will be telling, moving forward, is just how seriously the researchers take their own work, as they have been handed a set of assumptions for problem-solving within their domain from the astrophysicists: They are told that charge separation is rare in space; that electricity does not do anything of any importance in the cosmos; and that -- unlike smaller-scale matter -- large-scale matter (bodies in space) do not acquire and trade electrical charge. There is by now ample evidence that these assumptions are verifiably false. And, what we are waiting for is the representatives of the various disciplines to develop the courage necessary to question the scientific framework that they've been handed.

To be clear, any and all critics must familiarize themselves with the totality of the arguments (evident within the Thunderbolts Pictures of the Day) before claiming to know the answer. Those who argue against these claims without reading them are stalling the real conversation.

Obviously, the arrow points to a small line of possible mounds of salts or some other whitish compound that is lower in height in that area than the line further up and to the right in the picture. The sunlight is coming from the right, so that there is a dark shadow to the left of the line to which the arrow points. A little further up from the arrow, the white line becomes a series of "dots and dashes", then appears to disappear in a northerly heading at the start of the first long shadow that is above the slice to which the arrow points. The presence of the "salts" appear to diminish along the right side of the longer shadow, but it may be that the salts have tumbled over the precipice and down into the longer shadowy area which is up a bit from the arrow.

I don't understand why the researchers zeroed in on that one small area without providing a closer photo with higher resolution. The terrain all around appears flattish with some areas of depression that may have been created by multiple impacts to make continuous rows of small craters that almost look like graves. But that might be because the craters appear to be too close together at that distance from the camera. However, as in many flattish regions of Mars, the terrain in all four corners is higher in elevation than the terrain in the middle of the picture.I see no evidence of early volcanic lava action in this picture in spite of its flatness. The amount of dust in the area is probably of sedimentary origin and the rilles could be the remnants of a very large salty sea or saltwater lake which boundary was the rilles on one side, and a much higher elevated terrain on the other side, also.

It appears to me that at one time the rilles may either have surrounded the area up to and including the sloped terrain at the bottom and the left side in the picture, and the possible rilles at the bottom may have eroded faster than the ones at the top. The liquid water may have become ice and then sublimated away gradually, then a water source filled the depression again and again and sublimated again and again, leaving the remnants of salts. There may even have been a "spring" of sorts that could have been the source of water that froze. The arrow just might be pointing to a small source of water. . .a spring, and the other dark shadows may be sources of liquid also. I notice that the long dark shadows to the left of the rilles at the top of the picture and on the right side don't seem to all follow the CONTOURS of the rilles. If the researchers could provide us a zoomed in picture, we/they should be able to determine if those dark shadows are, indeed a source of liquid H2O.

LOL - my above post had to do with the SECOND picture in the article. I hadn't even looked at the first one, but now I have. The first picture has to be some kind of joke, in that the squiggly line that the arrows point to are obviously stress lines caused by shifting of the terrain through stresses from underground, but not necessarily from volcanic action. It might even have been caused by stresses from a passing large asteroid or a tidal action from one of the Mars moons.I misunderstood, that the second picture is of the Moon, not Mars. . .I apologize for wasting your time.